1. Field of the Invention
The present invention relates to a developer feeding apparatus and a developing apparatus applied to an image forming apparatus.
2. Description of the Related Art
Conventionally, an image forming apparatus using an electrophotographic image forming process adopts a process cartridge system in which an electrophotographic photosensitive member and a process unit acting on the electrophotographic photosensitive member are integrated into a cartridge and the cartridge is made removable from the main body of the image forming apparatus.
According to the process cartridge system, the apparatus can be maintained by the user himself (herself) without relying on maintenance personnel and thus, operability can significantly be improved. Therefore, the process cartridge system is widely used in electrophotographic image forming apparatuses.
A developer feeding apparatus is integrated in this kind of process cartridge to feed a developer (toner) to a developing roller by a developer feeding member (toner feeding member) provided in the developer feeding apparatus being rotated.
Some developer feeding apparatuses have a unit for changing the rotational speed of the toner feeding member by which the number of revolutions of a motor is controlled in accordance with a remaining amount of toner to change the number of revolutions of the toner feeding member (Japanese Patent Application Laid-Open No. 01-84266).